How to use phenylephrine (PE) as a push pressor?

From the Guidelines

Phenylephrine should be administered as a vasopressor through intravenous (IV) push or continuous infusion to treat hypotension, starting at a dose of 0.1 μg/kg/min, which may be titrated up to obtain target blood pressure, as recommended by the most recent expert consensus guidelines 1.

Key Considerations

• Phenylephrine works as a pure alpha-1 adrenergic receptor agonist, causing peripheral vasoconstriction which increases systemic vascular resistance and blood pressure.
• Ensure adequate volume resuscitation before starting vasopressors, as phenylephrine will be less effective in hypovolemic patients.
• Always monitor the patient's blood pressure, heart rate, and tissue perfusion continuously during administration.
• Be aware that phenylephrine can reduce cardiac output and cause reflex bradycardia, so it's best used for hypotension with normal or elevated heart rate.

Administration Guidelines

• For IV push, prepare phenylephrine by diluting 10 mg in 100 mL of normal saline to create a 100 mcg/mL solution.
• Administer bolus doses of 50-200 mcg (0.5-2 mL) every 1-2 minutes as needed to achieve the desired blood pressure, typically aiming for a mean arterial pressure (MAP) of 65 mmHg or higher.
• For continuous infusion, use the same dilution and start at 0.1 μg/kg/min, titrating by 0.1-0.2 μg/kg/min every 10-15 minutes based on blood pressure response, as recommended by expert consensus guidelines 1.

Special Considerations

• Phenylephrine is not recommended as a first-line treatment for septic shock, except in specific circumstances, such as when norepinephrine is associated with serious arrhythmias or when cardiac output is known to be high and blood pressure persistently low 1.
• The use of phenylephrine should be guided by the most recent expert consensus guidelines and should be tailored to the individual patient's needs and response to treatment.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Dilute before administration ( 2 SECT 2. 1). Dosing for Perioperative Hypotension • Intravenous bolus administration: 50 mcg to 250 mcg ( 2 SECT 2.4) • Intravenous continuous infusion: 0.5 mcg/kg/minute to 1.4 mcg/kg/minute titrated to effect ( 2 SECT 2.4) Dosing for Patients with Vasodilatory Shock • Intravenous continuous infusion: 0.5 mcg/kg/minute to 6 mcg/kg/minute titrated to effect ( 2 SECT 2. 5)

To use a phenylephrine push presser, dilute the solution before administration. For intravenous bolus administration, the recommended dose is 50 mcg to 250 mcg. For intravenous continuous infusion, the dose is 0.5 mcg/kg/minute to 1.4 mcg/kg/minute for perioperative hypotension, or 0.5 mcg/kg/minute to 6 mcg/kg/minute for vasodilatory shock, titrated to effect 2.

From the Research

Preparation and Administration

• To use a phenylephrine push presser, it is essential to follow proper preparation and administration guidelines 3, 4, 5.
• Phenylephrine can be administered peripherally, but it is crucial to use low-concentration solutions and follow safety protocols to minimize the risk of complications 4, 5.
• The dosage and administration rate may vary depending on the patient's condition and the desired effect, but typical doses range from 0.1 to 0.5 mg, administered over 1-2 minutes 3.

Safety and Efficacy

• Studies have shown that peripheral administration of phenylephrine is safe and feasible in various clinical settings, including neurocritical care units and operating rooms 4, 5, 6.
• Phenylephrine has been compared to other vasopressors, such as epinephrine and norepinephrine, and has been found to be effective in increasing blood pressure and maintaining cerebral perfusion pressure 3, 6.
• However, dosing errors and complications can occur, emphasizing the need for careful monitoring and adherence to safety protocols 3, 5.

Specific Clinical Scenarios

• In patients undergoing general anesthesia for major noncardiac surgery, phenylephrine can be used as a first-line vasopressor to treat hypotension 6.
• In neurocritical care units, phenylephrine can be used to maintain cerebral perfusion pressure and treat hypotension, with careful monitoring and safety protocols in place 4, 5.
• In coronary artery bypass grafting, phenylephrine can be used to increase blood flow in the radial artery used as a coronary bypass conduit 7.